heterophylly: leaves above and below water

[lesley]

I'm looking for a plant to use for a Botany lab demo which shows heterophylly, a distinct difference in the appearance of the above- and below-water leaves. The classical example is Myriophyllum heterophyllum, but I have a feeling that that one might not be as hardy in a tank as some other plants may be. Does anyone know of an easy to grow, easy to get plant that has different submerged/emersed leaves?

Thanks in advance for any suggestions!

 

[Squawkbert]

Marselia quadrifolia - there's even been some (old) papers on how to induce the 2 forms by manipulating light...(in M. vestita) - John J. Gaudet, Dept. Botany, U.C. Berkeley

M. quadrifolia is a 4 leafed clover emergent, looks more like M. minuta if immersed deep enough.

Bacopa leaves & other species show differences too, but they're more subtle.

 

[Quartermain]

I was thinking that Hygrophila difformis might be also be good chioice. It is very hardy and easy to grow, will not drop its submersed leaves when growing above the surface, and is very highly differentiated morphology between submersed and emersed growth.

 

[soobie]

Waterlilies- Nymphaea sp.

 

[lesley]

Thank you all for your suggestions. I liked the Marsilea or Nymphaea myself, but my collaborators want something more um... stemmy, to show the changes along a single axis. The Hygro is a good idea. I'll check my LFS.

THANKS!

 

[plantbrain]

Why not come out to aquatic weed lab at UC Davis?
We have several species you can use.

I have some Pondweeds, Myriophyllum aquaticum, Echinodorus etc.
I can give you the Myrio or some pondweeds.

If you want someone that did their dissertation on heterophylly in aquatic plants right here, Dr Tom Goliber here at UCD.

Almost every angiosperm plant exhibits heterophylly..........cotoylendens etc......

A good book on the topic: Sculthorpe's The Biology of Aquatic Vascular Plants, I think there is a copy in the UCD library.
It's out of print I believe but folks can still find it.

Sagitteria is another, I have some submersed form plants at the lab and some good pics of both types. Those and the Sword plants are from/collected from the San Joaquin River near HYW 99 a few miles from Fesno.






Regards,
Tom Barr

 

[lesley]

Plantbrain,

Ha! That's kind of funny. Tom Goliber is my supervisor, and the one who was asking me to look for plants. I know he had tried to get in touch with Lars Anderson, but didn't get a response, and he didn't know who else to contact at the weed lab.

I found some Hygrophila difformis and it has the features that we were looking for, stem plant, heterophyllic leaves along a single axis. So now it's just a question of whether it will grow well enough under the conditions that we are able to provide.

If it doesn't work out, I might try to get in touch with you again.

Thanks!
Lesley

 

[plantbrain]

I have some parrot's feather, a weed, growing out there right now if you want some. It's plenty hardy, more so than the Hygrophila.

Stop by. I can leave a bag for you.
H. difformis is easy and should present no issues for growth or the two types.
Go with that if it works.

Adding CO2 will increase the rate of submersed growth about 10-20X.
DIY CO2 works well in small submersed cultures.

I think anatomical differences are a good thing to look at also, the cuticle, stomata, lacunae, drupes, raphids etc, lack of root hairs in water column root formation etc

Regards,
Tom Barr